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		<title>three.js webgl - ShadowMapViewer example </title>
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		<div id="info">
		<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - ShadowMapViewer example by <a href="https://github.com/arya-s">arya-s</a>
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import Stats from 'three/addons/libs/stats.module.js';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
			import { ShadowMapViewer } from 'three/addons/utils/ShadowMapViewer.js';

			let camera, scene, renderer, clock, stats;
			let dirLight, spotLight;
			let torusKnot, cube;
			let dirLightShadowMapViewer, spotLightShadowMapViewer;

			init();

			function init() {

				initScene();
				initShadowMapViewers();
				initMisc();

				document.body.appendChild( renderer.domElement );
				window.addEventListener( 'resize', onWindowResize );

			}

			function initScene() {

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 1000 );
				camera.position.set( 0, 15, 35 );

				scene = new THREE.Scene();

				// Lights

				scene.add( new THREE.AmbientLight( 0x404040, 3 ) );

				spotLight = new THREE.SpotLight( 0xffffff, 500 );
				spotLight.name = 'Spot Light';
				spotLight.angle = Math.PI / 5;
				spotLight.penumbra = 0.3;
				spotLight.position.set( 10, 10, 5 );
				spotLight.castShadow = true;
				spotLight.shadow.camera.near = 8;
				spotLight.shadow.camera.far = 30;
				spotLight.shadow.mapSize.width = 1024;
				spotLight.shadow.mapSize.height = 1024;
				scene.add( spotLight );

				scene.add( new THREE.CameraHelper( spotLight.shadow.camera ) );

				dirLight = new THREE.DirectionalLight( 0xffffff, 3 );
				dirLight.name = 'Dir. Light';
				dirLight.position.set( 0, 10, 0 );
				dirLight.castShadow = true;
				dirLight.shadow.camera.near = 1;
				dirLight.shadow.camera.far = 10;
				dirLight.shadow.camera.right = 15;
				dirLight.shadow.camera.left = - 15;
				dirLight.shadow.camera.top	= 15;
				dirLight.shadow.camera.bottom = - 15;
				dirLight.shadow.mapSize.width = 1024;
				dirLight.shadow.mapSize.height = 1024;
				scene.add( dirLight );

				scene.add( new THREE.CameraHelper( dirLight.shadow.camera ) );

				// Geometry
				let geometry = new THREE.TorusKnotGeometry( 25, 8, 75, 20 );
				let material = new THREE.MeshPhongMaterial( {
					color: 0xff0000,
					shininess: 150,
					specular: 0x222222
				} );

				torusKnot = new THREE.Mesh( geometry, material );
				torusKnot.scale.multiplyScalar( 1 / 18 );
				torusKnot.position.y = 3;
				torusKnot.castShadow = true;
				torusKnot.receiveShadow = true;
				scene.add( torusKnot );

				geometry = new THREE.BoxGeometry( 3, 3, 3 );
				cube = new THREE.Mesh( geometry, material );
				cube.position.set( 8, 3, 8 );
				cube.castShadow = true;
				cube.receiveShadow = true;
				scene.add( cube );

				geometry = new THREE.BoxGeometry( 10, 0.15, 10 );
				material = new THREE.MeshPhongMaterial( {
					color: 0xa0adaf,
					shininess: 150,
					specular: 0x111111
				} );

				const ground = new THREE.Mesh( geometry, material );
				ground.scale.multiplyScalar( 3 );
				ground.castShadow = false;
				ground.receiveShadow = true;
				scene.add( ground );

			}

			function initShadowMapViewers() {

				dirLightShadowMapViewer = new ShadowMapViewer( dirLight );
				spotLightShadowMapViewer = new ShadowMapViewer( spotLight );
				resizeShadowMapViewers();

			}

			function initMisc() {

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				renderer.shadowMap.enabled = true;
				renderer.shadowMap.type = THREE.BasicShadowMap;

				// Mouse control
				const controls = new OrbitControls( camera, renderer.domElement );
				controls.target.set( 0, 2, 0 );
				controls.update();

				clock = new THREE.Clock();

				stats = new Stats();
				document.body.appendChild( stats.dom );

			}

			function resizeShadowMapViewers() {

				const size = window.innerWidth * 0.15;

				dirLightShadowMapViewer.position.x = 10;
				dirLightShadowMapViewer.position.y = 10;
				dirLightShadowMapViewer.size.width = size;
				dirLightShadowMapViewer.size.height = size;
				dirLightShadowMapViewer.update(); //Required when setting position or size directly

				spotLightShadowMapViewer.size.set( size, size );
				spotLightShadowMapViewer.position.set( size + 20, 10 );
				// spotLightShadowMapViewer.update();	//NOT required because .set updates automatically

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

				resizeShadowMapViewers();
				dirLightShadowMapViewer.updateForWindowResize();
				spotLightShadowMapViewer.updateForWindowResize();

			}

			function animate() {

				render();

				stats.update();

			}

			function renderScene() {

				renderer.render( scene, camera );

			}

			function renderShadowMapViewers() {

				dirLightShadowMapViewer.render( renderer );
				spotLightShadowMapViewer.render( renderer );

			}

			function render() {

				const delta = clock.getDelta();

				renderScene();
				renderShadowMapViewers();

				torusKnot.rotation.x += 0.25 * delta;
				torusKnot.rotation.y += 2 * delta;
				torusKnot.rotation.z += 1 * delta;

				cube.rotation.x += 0.25 * delta;
				cube.rotation.y += 2 * delta;
				cube.rotation.z += 1 * delta;

			}

		</script>
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